Wall Street tumbles at open on global demand concerns

There are concerns about weak global demand and its potential impact on the US economy and businesses

US stocks opened sharply lower on Thursday, after the S&P 500 closed at its lowest in six months, amid concerns about weak global demand and its potential impact on the U.S. economy and businesses.

The Dow Jones industrial average fell 169 points, or 1.05 percent, to 15,972.74, the S&P 500 lost 21.37 points, or 1.15 percent, to 1,841.12 and the Nasdaq Composite dropped 67.86 points, or 1.61 percent, to 4,147.46.